Hydraulic shock absorber



. p 1931- E. W. JOHNSON 1,822,406

HYDRAULIC SHOCK ABSORBER Filed Dec. 14. 1928 2 Sheets-Sheet 1 7 vsrrron9,9 73 mm WM I 1 W, W (2 W Sept. 8, 1931. E. w. JOHNSON HYDRAULIC SHOCKABSQRBER Filed Dec. 14, 1928 '2 Sheets-Sheet Patented Sept. 8, 1931UNITED STATES PATENT OFFICE ERNEST WILLIAM JOHNSON, OF LONDON, ENGLAND,ASSIGNOR OF ONE-HALF TO LUVABZ LIMITED, OF LONDON, ENGLAND, A BRITISHCOMPANY HYDRAULIC sHocK ABSORBER Application filed December 14, 1928.?Serial No. 326,120.

This invention is for improvements in or relating to hydraulicshock-absorbers and more particularly to shock-absorbers of the typeshown and described in the specification of United States Letters PatentNo. 1,578,319, dated 18th July, 1925. I

It is an object ofthe'present invention to provide a shock-absorberwhich will be robust and cheap to manufacture. V

ll) Itis another object of the present invention to provide ashear-absorber in which certain parts canv be formed as stampings, andin which the parts can be readily assembled without skilled fitting.

a it is a further object of the invention to reduce the overalldimensions of such devices whereby their weight and the cost ofproducing them is also reduced. V V p Further objects of the presentinvention It-ion of'a preferred embodiment of the invention asllustrated 1n the accompanying drawings in winch:

. r igure 1 1s a perspective view showing, in

cordance with the invention;

Figure2 is a viewto a larger scale thanv Figure 4 is a detail viewshowing the device in section along thebentj line tl: of Figure 3 withcertain parts omitted for the sakeof clearness; 1

Figure 5'is a detail sectionalview along the line 55 of Figure 3,certain parts being omitted for the sake of, clearness;

Figure 6 isa similar 'view to Figure 5 showing a detail modification, v

Figure 7 is a view showing a part of the device.

and

Figure 9 is a view'similar to Figure l, but showing a modification.

Like reference numerals indicate like parts in all the figures of thedrawings.

The shock-absorber is built up on an end:

late 10 which is formed with holes 11, wh e- "ill be apparent from thefollowing descrip:

elevation, a shock-absorber constructed in ac- Figure 8 is a detailsectionalview of a band,

by it can be mounted in the vehicle-chassis. This plate is formed with acentral spigot 12 at the centre of Which is a circular bore 13 and whichhas also a second circular bore 14 located above the central bore 13.The endplate is further formedwith a circular flange 15. which isconcentricwith the spigot and projects outwardly from the same face ofthe endpla'te. V3

Mounted on the end-plate is an inner casing 16 which encloses a Workingchamber 17 for the reception of the working liquid. The inner casing isformed as a pressing and having a cylindrical wall 18 and an annularWall a flange 22, the periphery of which is formed with six equallyspaced serrations 23. Carried in the tubular extension 20 is a bearing24 formed with a collar 25 which abuts against the cham'fered surface21. The outer end of the bearing is threaded and carries a nut 26 whichis screwed tightly against the end of the extension 20 so as to hold thebearing in position, The outer surface of the nut 26 is cylindrical andforms a continuation of the outer surface of the extension 20. Journalled inthe bearing 24 is a spindle 27, one

'endiof which projects outwardly from the casing 16, and the other endof which is sup- :ported. in the circular-bore 13 in the end- 1 plate10. A vane 29 is secured to that part 28 of the spindle 27 that lieswithin the chamber 17 and has the formof a blade having a rounded'boss.1 This boss is shown integral with the spindle, but it may be flexiblyse-. curedthereto in any convenient manner.

An abutment 30 is secured within the casing, whichis divided into twoparts by the abutment and the vane. Referring to Figure 2 it willbe'seen that the abutment is bounded by'twolcoaxial cylindrical walls 31and 32, which are in contact respectively with the inner surface of thewall 18 of the casmg 16.

and the outer surface of the collar 28, and

thronghway, the; diameter of; which is; the, same as the-externaldiameter of the collar- 28. After being bored, the bar is cut-off 9,into. lengths .equalto the length of the abutment and divided .alongradial .pla'nes',.into

four abutments in any suitable manner. Each segment so made willhaveetwo accu rately concentric surfaces which will fit snugly in place.At oneendof therabutment a" spigot 35 is provided, which spigot isreceived A? in the bore 14in the endpliate 10, and the lgother end istapped'at' 36 and 37 for two 5 screws ;38,lwhich project-throughsuitable openings in the 11 19 of the inner casing "andhold the abutmentthereto. Theabut- ,inent isformed with a circular bore39'at its endoppos'itethe spigot- 35, a tapped concen tric bore 40 of reduceddiameter which forms a continuation of the bore 39, and 'a concentricpassa-geAd forming a continuation-of the; tapped bore 40 and tfelrninating near the root otthe spigot 35. Apassagef42 extends from -'-thebore-40-to -the radial surface "34: and a similarpassage 43extends fromthe'passage -4c1-to thelradial surface 33 (see Figures 4 and 3A ballvalve 44 is-located iii-the bore 410 andis pressed'by a .-sprin'g-4E5-soas to; close -the passage 41-. 1 An adjusting screw46 is l screwedfintothe bore and serves both as an abutment for the spring 15 andas alimit-f ing stop voft-he ball-valve 4A. A The-head of 1 screw tti islocated i-n-the bore 39 and is slotted K at 4:7 to provide means forrotating the-screw v Q to adjust th'eload on-t he valve;

Referring to'Figures 3 and it it will beseen t-hat when the vane isrotated counterclockwiseithe ivorking liquid can pass freely :througlrthe pas'sagesAiigAQand142 but when" the (vane is rotated clockwise the:valve 44 s will {prevent any liquid from passing -througlrthese Tpassages. -The following J means, are providedior'allowing a restrictedI flow-whem the vane is rotating clockwise so" jas to produce therequired damplng action.

=Two' 1'aassages-f 48 and extend' from the bore fBQtQ-fth'radial surface33 and theloylindri 'cal suriace-32 respectively, and a thi-rd'pas-" "sage 5'Olextends"fro jmthe passage 49 toithe radial surface 34.A tapped hole- 51;;6X-

ltends' from outside-the inner casing 16 -tlirough the latter andtheabutnie'iit and r t v a i H.) ,0 opens intothe bore 39. ThIS hole is nallgn- 1nenew-jur the passage 49 and a screw:

threaded needle-valve 5 2 isre ceived in it.

-"=-Thepoint ofgth'e'valve' 52 reaches into-the passage'fdfi) and obstr'ucts it soas topermit only' arestrictedfiowpf liquid through 1t.

-,,WVhen the valve i s correctly set, it is locked in 1 -position by alock-nut 53l -Theyalve'52 also extends through the slot 47 in theadjusting screw 46 so as to lock this latter part against rotation (asshown in Figures 2 and 3) Mounted on the end-plate 10 is an outer casing54 which encloses the inner casing and constitutes a recuperator chamber55 surrounding the ,workingchaanber. t At its top, the outer casingisprovided with an orifice closed by a screw-cap 56 and arranged inalignment. with thei,needlesvalve =52. The orificei serves las a fillingorifice for the recuperator-chamber and also to give access to ,theneedle valve so that it may be adjusted.

Means are provided for replenishing the workingt chamben 17 with Workingliquid from the recuperator-chamber 55. .Referring to Figures, 3 and 4,threeshallow recesses 57 are formed inthe exterior "of the:wa1lf18-ot'the inner casing towards the bottoin" thereof, and twosimilar ,recesses59 towards the topthereof A slot ;58 extends fromeachof the depressions 57 to the inside ofthe casing anda circular hole60 extends from eaeh'of the depressionsbfl to the inside .of the casing.The holes '60 are located in that part ofthewall 18 which isin contactterminates in'a hole 66, and which are spaced roiind the bandi so as .toregister one with each er the'depression's57 or 59. ..In each of thecavities so formed, a ball-valve 67 isreceiv ed. In order that the bandmaybe correctly, mounted on the inner casing it has a locating pip 68.pressed ut of'it, and the inner casing has a co-operatingdepression "69formed in it (see Figure 4).; The band is sheathed in lead as showninFigure 8 in order to provide an, I oiltight. oint between it and theinner casing, has i tstwo ends 7 0 andi'l turned'outwardly and securedtogetherby a nut screw 72 passingthrough item and: dampi ths ba Ontd ts- Instead of clamping th'eband 6d in position, ,the b and may becontinuous and may be ;shrunk' on,; as shown, in- Figure 9. The valves67 at .the b.ottom of the. casing permit ,thefree passage of liquid.from the'recupera tor chamber 55, to theworking chamber, but ,prevent;retnrns movement thereof as described in the aforesaid priorspecification.

g'ThQ valves 6 5;at: the top of the casing permit of any air that mayleak into the working :cliamberbeing forced out of it withoutallowenough up for them not to be covered by the escape vane 29 when thelatter is in either extreme which is formed with six corrugations 74c."

Qne end of the outer casing is partly closed y an annular end-wall whichis formed "ith a central tubular extension 76. The other end of theouter casing is open, and this end of the cylindrical wall isturned-outwardly to form a flange 77. The bearing 24 and nut 26 extendinto and fit snugly within the tubular extension 76. The top of the nut26 and the tubular extension 20 is removed, as shown at 78 (Figure 5),so to form a passage between the nut'26 and the tubular extension 76.Alternatively, as shown in Figure 6, the tubular extension 76 may beindented on its inner surface, as shown at 80, in order to form asimilar passage 7 9. The object of this passage 7 9 is tov allow otjanyworking liquid which may leak from the working-chamber along the spindle57, and collect within the tubular extension76, to from the tubularextension into the recuperator-chamber. An internal circumferentialprojection is formed in the tubular extension 76 at 81, and that portionof the extension beyond this projection is threaded externally for thereception of a cap 82. A. trough-shaped packing-ring 83 is locatedbetween the end of the tubular extension 76 and the spindle 27. Locatedwithin the tubular extension and abutting against the projection 81 isan abutment-ring 84, which is termed with a conoidal surface againstwhich one side of the trough-shaped packing-ring abuts and which alsobears against the inner surface of the other side of the packing-ring at86. such that when the cap 82 is screwed down, it presses thepacking-ring against the abutment and the latter expands the packingringinto sealing contact with the spindle. The spindle 27 has secured to itstree end the usual lever 87, the end or" which is con nected to the axleof the vehicle by a link 88, also in the usual manner.

The shock-absorber is assembled in the following manner :-The bearing 24is secured in place and the spindle with the vane secured on it ismounted in the bearing. The ball-valve 4a is assembledin the abutment 30and the load on the valve is adjusted "by means of the set-screw 46; Theabutmentis then secured in position in the inner casing. The ball-valves67 are placed in the depr ssions 57 and with the aid of a little and theband 64. is slipped into position on the casing and clamped thereon. Theneedlevalve 52 is then. placed in position and ad,- justed so as to givethe required damping action and to lock the screw 46. V The open end ofthe inner casing is then forced under pressure onto the spigot 12 on theends-plate,

The. arrangement is;

and the flange 22 is riveted to the end-plate by means ot rivets 89. Bymeans of this spi ot-joint between the end-plate and the inner casing,an oil-tight joint between these two parts is ensured. The outer casing54 is mounted on the end-plate with its corrugations 7ain radialalignment with the serrations :3 in the flange 22 of the inner casing,and is secured thereto by screws passing through the flange 77 in radialalignment withthe corrugations T l. 1

The operation of the device will be readily understood from the aboveand is the same as that described in the aforesaid prior specification.lVith the parts arranged as illustin-ted, the liquid in the workingchamber will otter resistance to the movement of the vane 1n theclockwise direction as viewed in FIQHFQSQ and l, as the valve 44: Wlllbe forced upon its seat, but movement of the vane in the.

opposite direction will be readily permitted.

It will be seen that wlth the present mvention the various parts can becheaply manufactured so as to fit accurately together and that the wholedevlce can be rapidly as" sembled. lit will be noted that owing to theprovisions of the corrugations 74 in the outer casing and to thestaggered arrangement of the rivets S9 and screws 90, the two casingscan be secured to the end-plate 10 by means of flanges without anysubstantial increase in the dimensions of the device being necessary. Itwill also be seen that the needlevalve 52 can be readily adjusted toadapt the shock-absorber to the particular vehicle to which it is to befitted.

It is to be understood that the present invention is not restricted othe precise contional details described above and that without departingfrom the scope of the invention. r

I claim: v I

1. A hydraulic shock-absorber comprising an end-plate, an inner casingmounted thereonsand constituting a main working chamber forthe receptionof a working liquid, a vane in said chamber, a spindle secured to saidvane and projecting from said chamber, a cooperating abutment secured insaid chamber, an outer casing constituting a recuperator' chamber, whichouter casing is so mounted on :said end-plate that the worlc mg chamberis nested m the recuperator chamber, and which outercasing has its sidewalls corrugated to form external depressions therein extendingperpendicularly of the endplate, devicestor securing said outer casingto said endsplate, which devices are located in alignment with saiddepressions, devices:

for securing said inner casing to said endplate, which devices arelocated between said inner and outer casings in staggered relationshipto said external depressions, and means for automatically keeping theworking chanr modifications may be made therein 1 an end-plate, an innercasing formed of sheet 7 5; metal and pressed into shape, which innercasing is mounted on said end-plate and constitutes a working chamberfor the reception 'of a working liquid, a vane in said chamber,

' a spin'dle'secured to said vane and projecting fromsaid'chamber, aco-operating abutment secured in said chamber, an outer casingconstituting arecuperator chamber, which outer casing is so mounted onsaid end-platethat the workingchamber is nested in the recuperatorchamber, and which outer casing is formed of: sheet metal, pressed intoshape and has 'its' side -walls corrugated during the pressing operationto form external depressions' therein extending perpendicularly of 0 theend-pl'ate,--devices for securing said outer casir'ig; to said'end-platewhich devices are located in alignment with said depressions, de-

vices for securing said inner casing to said "end-plate, which devicesare located between 5 said inner and outer'casingsin staggeredrelationship to said external depressions, and means for automaticallykeeping the working chamber charged with working liquid fromthe'recuperator chamber.

A hydraulic shock-absorber comprising an end-plate, an inner casingmounted thereon and constituting a main working chamher for thereception of a working liquid, a vane insaid chamber, a spindle securedto i said vane and projecting from said chamber, a bearing for saidspindle, which bearing is mounted on said inner casing to extendoutwardlytherefrom, an outer casing constitutinga-recuperator chamber,which casing is somounted on said end-plate that the Working chamber isnested in the recuperator chamber, an outwardly directed tubularextension formed in said outer easing, into -which extension the freeend of said bearing reaches so as'to close the inner end thereof,

a'gland located atthe outer end of the extension through which gland thespindle passes, a passage, located between the bearing and theextension, and extending from the space 0 within the extension betweenthe gland and I bearing to the recuperator chamber, and means forautomatically keeping the working chamber charged with working liquidfrom t-herecuperator chamber.

5 4. A hydraulic sh'ockabsorber comprising an end-plate,-a' spigotformed in said endplate, an inner casing, constituting a main workingchamber for the reception of a working liquid, which casing is formed asan open 0 ended cylinder and has said spigot forced into its openendunder pressure, an outwardly directed annular flange surrounding "theopen end of said casing, an annular surface "on said end-plate againstwhich said -flange abuts, rivets passing through said flange and saidend-plate to secure them together, a vane in said chamber, aspindlesecured to sand vane and pro1ect1ngtrom said chamber, a co-operatingabutment secured in said chamber, an outer casing constituting arecuperator chamber which casing is so mounted on said end-plate thatthe working chamber is nested in the recuperator chamber, and means forautomatically keeping the working chamber charged with working liq- Iaid from the recuperator chamber.

5. A hydraulic shock-absorber comprising an end-plate, a spigot formedin said endplate, aninner casing, open at one end and constituting amain working chamber forthe reception of a: working liquid, which casingcomprises a cylindrical wall, an integral end-wall formed with anopening and partly closing one end of the casing, an integral tubularflange surrounding said opening, and an integral annular flangeextending outwardly from the cylindrical wall at the other end of thecasing and having its periphery formed with indentations, and whichcasing has the said spigot forced into its open end under pressure,rivets passing through said end-plate and said flange between saidindentations, a vane in said chamber, a spin dle secured to said vaneand projecting from said chamber, a co-operating abutmentsecured in saidchamber, a bearing for said spindle, which bearing is carried by saidtubular flange on the inner casing, an outer casing, constituting arecuperator chamber,

which casing is formed as an open ended c \'linder, having itscylindrical walls corrugated to form external depressions extendingparallel'to its axis, and having an outwardly directedflange formed init at its open end, means for securing said flange to said endp'late,which means are located in alignment with said corrugations and saidindentations in the inner case, and means for automatically keeping theworking chamber charged with w rking liquid from the recuperator cham-'ber. I

6. A hydraulic shock-absorber comprising an end-plate, an inner casingmounted thereon and constituting a main working Cl1ti111- her for thereception of a working liquid, a vane in said chamber, a spindle securedto said vane, and projecting from said chamber, a co-operating abutmentsecured in said chamber, an outer casing constituting a rcsaid innercasing so as to retain both said valve-members in position. v

7. A hydraulic shock-absorber comprising an end-plate, an inner casingmounted thereon and constituting a main working chamber for thereception of a working liquid, a vane in said chamber, a spindle securedto said vane and projecting from said chamber, a co-operating abutmentsecured in said chamber, an outer casing, constituting a recuperatorchamber, wiich casing is so mounted on said end-plate that the workingchamber is nested in the recuperator chamher, an air-release passageformed in said inner casing, a liquid admission passage formed in saidinner casing, a valve member in each said passage, a band that has asoft face, is formed with a passage to register with said air-releasepassage and a passage to register with said oil admission passage, andis secured on the outside of said inner casing so as to retain both saidvalve members in position, and means for contracting said band to clampit onto the casing.

8. A hydraulic shock-absorber comprising an end-plate, an inner casingmounted thereon and constituting a main working chamber for thereception of a working liquid a vane in said chamber, a spindle securedto said vane and projecting from said chamber, a co-operating abutmentsecured in said chamber, an outer casing constituting a recuperatorchamber, which casing is somounted on said end plate that the workingchamber is nested in the recuperator chamber, an air-release passageformed in said inner casing, an oil admission passage formed in saidinner casing, valve member in each of said passages, and a band formedwith a passage to register with said air-release passage and a passageto register with said liquid admission passage and secured on theoutside of said inner casing so as to retain both said valve-members inposition, a projection and a co-operating depression formed one on saidband and one on said inner casing.

-9. A hydraulic shock-absorber comprising an end-plate, an inner casingmounted there on and constituting a main working chamber for thereception of a working liquid, a vane in said chamber, a spindle securedto said vane and projecting from said chamber, a cooperating abutmentsecured in said chamber, which vane and which abutment divide the saidchamber into two parts, and which abutment is located in the upper partof said chamber and is in engagement with said casing over its topsurface, tWo air-vent passages, formed in said abutment, each opening onone end through said top surface, one communicating with one said partof the working chamber and the other communicating with the other saidpart, two air-release valves provided in said inner casing and locatedone in alignment with each said air-vent passage, at least one liquidadmission valve provided 111 said inner casing and located to-- in saidchamber, a spindle secured to, said:

vane and projecting from said chamber, a cooperating abutment secured insaid chamber, which vane and which abutment divide the said chamber intotwo parts, a passage extending through said abutment from one part ofsaid chamber to the other part, a screwthreaded needle-valve in theabutment, which valve reaches into said passage and extends through saidcasing so that it can be adjusted from without the latter, an outercasing constituting a recuperator chamber, which casing is so mounted onsaid end-plate that the working chamber is nested in the recuperatorchamber, a filling orifice formed in said outer casing in alignment withsaid needle-valve so that the latter can be adjusted,

through it, and means for automatically keeping the working chambercharged with working liquid from the recuperator chamberf 11. Ahydraulic shock-absorber comprising an end-plate, an inner casingmounted thereon and constituting a main working chamber for thereception of a working liquid, a vane in said chamber, a spindle securedto said vane and projecting from said chamber, a co-operating abutmentsecured in said chamber, which vane and which abutment divide the saidchamber into two parts, a passage extending through said abutment fromone part of said chamber to the other part, a screw-threadedneedle-valve in the abutment, which valve reaches into said passage andextends through said casing so that it can be adjusted from without thelatter, a second passage in said abutment also extending from one partof said chamber to the other part, a springloaded non-return valve insaid passage, an adjusting screw in said abutment, which screw isrotatable to vary the load in the valve and is locked from rotation bythe said needle-valve, an outer casing constituting a recuperatorchamber which casing is so mounted on said end-plate that the workingchamber is nested in the recuperator chamber, a filling orifice formedin said outer casing in alignment with said needie-valve so that thelatter can be adjusted through it, and means for automatically keepingthe working chamber charged with working liquid from the recuperatorchamber.

12. A hydraulic shock-absorber comprising an end-plate, an innercylindrical casing mounted thereon and constituting a main workingchamber for the reception of a- Working liquid, a spindle extendingoutwardly from said chamber, a Vane in said chamber having a round bosson said spindle, a cooperating abutment formed by dividing a cylinder,whereof the external diameter is equal to the internal diameter of theinner casing and the internal diameter is equal to 10 the externaldiameter of the boss, along radial planes into a plurality of similarblocks, each of which constitutes one abutment. and has two concentriccylindrical walls and two radial walls, which abutment'is secured insaid chamber, an outer casing constituting a .recuperator chamber, whichcasing is so mounted on said end-plate that the working chamber isnestedin the recuperator chamber, and means for automaticallykeeping theworkingchan'iber charged with Working liquid'from the recuperatorchamber.

In testimony whereof IafiiX my signature.

ERNEST -VVILLIAM JOHNSON.

